Appearing on The AM Show on Monday, the Education Minister said the review had only just started.

"We're only six weeks into a four-month consultation period," said Mr Hipkins. "I'm not in any way saying their voices aren't important or their views aren't important - that's what this process is all about. You get a range of views on the spectrum - people who think we're going too far, people who think we're not going far enough, and then a whole lot of views in between."

Mr Hipkins said the review included "a pretty extensive consultation process which includes a lot of principals".

"We've got a group of principals who are running consultation on our behalf throughout the country. The Principals Council's already had a meeting where they got 50 principals feeding their views in, we've got a meeting coming up in August with the Secondary Principals' Association where there will be 100 principals feeding their views into the process.

"We are trying to ensure that we get everybody's voices heard. We want to ensure that we hear from parents, students, employers, universities, polytechnics - we want everybody's voices heard in this.

"I was a bit disappointed they felt the need to take out a newspaper advertisement when the consultation's really just getting under way."

Chris Hipkins.
Photo credit: Newshub.

He said the group of 40 behind the newspaper ads "don't represent the views of all principals".

National leader Simon Bridges said at the weekend that the Government wasn't willing to listen to anyone that "disagreed with its bad ideas". Mr Hipkins denied this was the case.

"We actually want to hear from people who disagree with our way of thinking. This needs to be as far as possible a non-political process, one that's actually about what's best for education."